Biocompatible materials have been expected to be applied in various fields. Presently, artificial materials such as silicone, polyethylene, and polyurethane have been used in medical devices such as medical tubes and catheters. However, these materials are recognized as a foreign substance by a living body, so that there are some risks that the materials are denatured by adsorbing a protein or blood cells to surfaces thereof, and that the materials themselves are activated to cause rejection such as coagulation of blood.
On the other hand, as a material having a glycine-type betaine monomer as a side chain, a glycine-type betaine resin in which betaine is formed by treating with sodium chloroacetate or the like, a polymer obtained by homopolymerizing N,N-dimethylaminoethyl methacrylate, or copolymerizing N,N-dimethylaminoethyl methacrylate with another monomer, or the like has been known (see, for example, Patent Publications 1 to 3).
However, there are some disadvantages in these betaine resins that since it is difficult to perfectly terminate a betaine formation reaction, an N,N-dimethylamino group would remain in the resin, and the remaining N,N-dimethylamino group gives disadvantageous influence to biocompatibility.
Patent Publication 1: Japanese Patent Laid-Open No. Sho 51-9732
Patent Publication 2: Japanese Patent Laid-Open No. Sho 55-104209
Patent Publication 3: Japanese Patent Laid-Open No. Sho 56-92809